Lockable tank closure with expandable plug

ABSTRACT

A LOCKABLE CLOSURE FOR A FUEL TANK FILLER OPENING COMPRISING A FRAME CARRYING A RADIALLY EXPANDABLE, ANNULAR PLUG ENGAGEABLE WITH THE PERIPHERY OF THE FILLER OPENING TO LOCK THE CLOSURE THEREIN. THE ANNULAR PLUG IS EXPANDED RADIALLY BY A PLUG EXPANDING MEANS WHICH IS RESPONSIVE TO AXIALLY INWARD MOVEMENT OF A CENTRAL ACTUATOR CARRIED BY THE CLOSURE FRAME ADJACENT THE OUTER END THEREOF. THE CENTRAL ACTUATOR PROJECTS AXIALLY OUTWARDLY BEYOND THE OUTER END OF THE CLOSURE FAME PRIOR TO ACTUATION OF THE PLUG EXPANDABLE MEANS TO PROVIDE A VISUAL INDICATION THAT THE CLOSURE HAS NOT BEEN LOCKED. THE OUTER END OF THE CLOSURE FRAME CARRIES AN ANNULAR SEAL ENGAGEABLE WITH THE PERIPHERY OF THE FILLER OPENING. THE ANNULAR PLUG MAY BE FORMED OF AN ELASTOMERIC MATERIAL TO PROVIDE A SECOND ANNULAR SEAL WHEN THE CLOSURE IS LOCKED.

United States Patent 3,606,070 LOCKABLE TANK CLOSURE WITH EXPANDABLE PLUG Willard W. Shepherd, Whittier, Calif., assignor to Shepherd Machinery C0., City of Industry, Calif. Filed Oct. 6, 1969, Ser. No. 863,942 Int. Cl. B65d 39/12 US. Cl. 220-245 8 Claims ABSTRACT OF THE DISCLOSURE A lockable closure for a fuel tank filler opening comprising a frame carrying a radially expandable, annular plug engageable with the periphery of the filler opening to lock the closure therein. The annular plug is expanded radially by a plug expanding means which is responsive to axially inward movement of a central actuator carried by the closure frame adjacent the outer end thereof. The central actuator projects axially outwardly beyond the outer end of the closure frame prior to actuation of the plug expanding means to provide a visual indication that the closure has not been locked. The outer end of the closure frame carries an annular seal engageable with the periphery of the filler opening. The annular plug may be formed of an elastomeric material to provide a second annular seal when the closure is locked.

SUMMARY AND OBJECTS OF INVENTION The present invention relates in general to a closure for a tank filler opening, or the like, and, more particularly, to a closure of this nature which is capable of being locked and which can be unlocked only with a key to prevent fuel theft, tampering with the fuel tank, and the like.

In general, a primary object of the invention is to provide a closure which comprises a radially expandable, annular plug which is insertable into the opening and which, when radially expanded into engagement with the periphery of the opening, serves to lock the closure therein.

Another primary object of the invention is to provide means within and encircled by the annular plug for radially expanding same into locking engagement with the periphery of the opening.

A more specific and important object of the invention is to provide a lockable closure which includes: a closure frame having an outer end and having an inner end insertable into the opening; a radially expandable, annular plug carried by the closure frame adjacent its inner end and engageable, when radially expanded, with the periphery of the opening to lock the closure therein; a central actuator carried by the closure frame adjacent its outer end and movable axially from an outer position wherein it projects axially outwardly beyond the outer end of the closure frame and an inner position wherein it is at least approximately flush with the outer end of the closure frame; and plug expanding means responsive to axially inward movement of the actuator from its outer position to its inner position for radially expanding the plug into closure-locking engagement with the periphery of the opening.

It will be noted that, with the foregoing construction, the central actuator projects axially outwardly beyond the outer end of the closure frame when the closure is unlocked. Thus, it serves as a visual indicator of the unlocked condition, which is an important feature of the invention.

Another and important object of the invention is to provide key means engageable with the actuator for ice pulling same axially outwardly from its inner, locking position to its outer, unlocking position to release the plug from closure-locking engagement with the periphery of the opening. A related object is to provide a key means which is insertable into a cavity in the outer end of the actuator and which includes at least one projection engageable with an inwardly facing shoulder Within the cavity.

Another object is to provide a plug expanding means comprising a plurality of circumferentially spaced sectors connected to the actuator at their apices and having their larger ends in engagement with the plug, and movable from a cone-shaped configuration to substantially a discshaped configuration to radially expand the plug into locking engagement with the periphery of the opening, in response to axially inward movement of the actuator.

Another object is to provide a plug expanding means comprising a disc connected to the actuator and engaging an inner surface of the plug which converges axially inwardly so that the disc radially expands the plug in response to axially inward movement of the actuator.

Yet another object of the invention is to provide an annular seal on the closure frame adjacent its outer end and engageable with the periphery of the opening to prevent the escape of fuel.

Yet another object is to provide a closure wherein the plug is formed of elastomeric material and thus provides another seal supplementing the sealing action of the first seal mentioned. An alternative object is to provide a plug which is not necessarily elastomeric, but which is rendered radially expandable by forming it of a plurality of circumferentially spaced, flexibly interconnected segments.

The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the tank filler opening art in the light of this disclosure, may be achieved with the exemplary embodiments of the invention described in detail hereinafter and illustrated in the accompanying drawing.

DESCRIPTION OF DRAWING In the drawing:

FIG. 1 is a longitudinal sectional view of a lockable closure of the invention in its unlocked condition;

FIG. 2 is a view similar to FIG. 1, but showing the lockable closure inserted into a fuel tank filler opening and locked therein;

FIG. 3 is a view showing the lockable closure of FIGS. 1 and 2 partially in transverse section and partially in inner end elevation, FIG. 3 being taken as indicated by the arrowed line 3--3 of FIG. 1;

FIGS. 4 and 5 are fragmentary longitudinal sectional views respectively similar to FIGS. 1 and 2, but showing another embodiment of the invention; and

FIG. 6 is a fragmentary longitudinal sectional view showing still another embodiment of a radially expandable locking plug of the invention.

EXEMPLARY EMBODIMENT OF INVENTION FIGS. 1 to 3 These figures of the drawing illustrate a lockable closure 10 of the invention which is insertable into and adapted to be locked in a fuel tank filler opening 12, or the like.

The closure 10 includes a frame 14 having an outer end 16 and having an inner end 18 insertable into the opening 12. The outer end of the closure 14 is formed by an annular disc 20 which is preferably so shaped that the outer end of the closure frame is flush with the outer surface 22 around the opening 12, whereby to minimize drag in aircraft installations. The annular disc 20 carries an O-ring 24 in an external annular groove 26, the O- ring being engageable with the periphery of the filleropening 12 to provide a fluid tight seal.

The inner end 18 of the closure frame 14 is formed by a disc 28 spaced inwardly from the disc 20 by circumferentially spaced, shouldered pins 30.

Disposed between and encircling the space between the outer end inner discs 20 and 28 is a radially expandable, annular plug 32 of elastomeric material which, when radially expanded, engages the periphery of the opening 12 to lock the closure in the opening. Since the plug 32 is formed of elastomeric material, it also provides an additional seal between the closure 10 and the periphery of the opening 12, supplementing the sealing action of the O-ring 24. The radially inner surface of the annular plug 32 is provided therein, adjacent the axially inner end of the plug, with an annular groove 34 for a purpose to be described.

The closure 10 includes a central actuator 36 carried by the closure frame 14 adjacent its outer end 16 and movable axially from an outer position, FIG. 1, wherein it projects axially outwardly beyond the outer end of the closure frame, and an inner position, FIG. 2, wherein it is at least approximately flush with the outer end of the closure frame. More particularly, the actuator is axially movable in a central bore 38 in the disc 29, being sealed relative thereto by an O-ring 40 in an annular groove in the wall of the bore 38.

The actuator 36 operates a plug expanding means 42 in response to axially inward movement of the actuator from its outer position to its inner position, to radially expand the plug 32 into closure-locking engagement with the periphery of the opening 12. The plug expanding means 42 comprises circumferentially spaced sectors 44 connected to the actuator 36 at their apices and having their larger ends disposed in the internal annular groove 34 in the axially outer end of the plug 32. The apices of the sectors 44 are connected to the actuator 36 by disposing them between the axially inner end of the actuator and the frusto-conical head 46 of a screw 48 threaded into the axially inner end of the actuator. The pins 30 extend through radially elongated slots 50' in the respective sectors 44 to guide the sectors for movement to be described.

When the actuator 36 is in its outer, nonlocking position, the sectors 44 form an axially-outwardly-convergent cone. When the actuator 36 is in its inner position, the sectors 44 form substantially a disc to radially expand the axially inner end of the plug 32 outwardly into locking engagement with the periphery of the opening 12. As will be apparent from a comparison of FIGS. 1 and 2, the sectors 44 constitute a toggle mechanism which moves over center as the actuator 36 is displaced from its outer position to its inner position. Thus, the various parts of the closure 10 tend to remain in the positions shown in FIG. 2.

The closure 10 may be locked readily by merely pushing axially inwardly on the outer end of the actuator 36 to displace it from its nonlocking position, FIG. 1, to its locking position, FIG. 2, in which it will remain. Thus, the closure 10 may be locked by service personnel without a key, which is an important feature. Also, it will be noted that, when the closure 10 is not locked, the actuator 36 projects axially outwardly beyond the outer end 16 of the closure frame 14 to provide a visual indication that the closure 'has not been locked, which is an important feature.

The invention provides key means 52 engageable with the actuator 36 for pulling same axially outwardly from its inner, locking position to its outer, nonlocking position to release the radially expandable plug 32 from closure-locking engagement with the periphery of the opening 12. In the particular construction illustrated, the key means 52 comprises a T-shaped key 54 provided at its inner end with circumferentially spaced detents 56 spring biased radially outwardly. The detented portion of the key 54 is insertable into a cavity 58 in the outer end of the actuator 36 through a reduced-diameter opening 60 which cooperates with the cavity to provide an inwardly facing annular shoulder 62. The detents 56 are engageable with this shoulder to cause the actuator 36 to move axially outwardly from its inner position to its outer position in response to a pull force on the key 54. The spring-biased detents 56 are capable of resisting this pull force because the latter needs be sufiicient only to cause the toggle mechanism formed by the sectors 44 to go over center.

Considering the operation of the closure 10 as used on a private airplane, for example, when the pilot desires fuel, it is merely necessary for him to insert the detented end of the key 54 into the cavity 58, and pull outwardly on the actuator 36 to unlock the closure 10. Alternatively, this can be done by the attendant who will do the refueling. Then, the pilot pockets the key and the attendant, when refueling has been completed, locks the closure 10 by pushing inwardly on the actuator 36 with his thumb This procedure results in minimizing the possibiilty of having the key 54 fall into the hands of unauthorized persons, which is an important feature.

FIGS. 4 and 5 These figures illustrate a lockable closure for use in an opening 112. The closure 110 is similar in many respects to the closure 10 so that only the differences will be described. For convenience, the parts of the closure 110 corresponding to parts of the closure 10 will be identified by numerals higher by 100.

Thus, the closure 110 includes a frame 114 carrying a radially expandable elastomeric plug 132. The latter has a radially inner surface 134 which converges axially inwardly.

The actuator 136 of the closure 110 has connected thereto a plug expanding means 142 comprising simply a disc 144 secured by a screw 148, and having holes for the guide pins 130. The periphery of the disc 144 is engageable with the axially convergent inner surface 134 of the plug 132.

As will be apparent, to lock the closure 110 in the open ing 112, it is merely necessary to press inwardly on the outer end of the actuator 136, whereupon the disc 144 slides axially along the axially convergent inner surface 134 of the plug 132 to radially expand the plug out Wardly into locking engagement with the periphery of the opening 112, as suggested in FIG. 5. The detented portion of the key 54 may be inserted into the cavity 158, and then pulled axially outwardly to unlock the closure 110.

FIG. 6

This figure of the drawing shows an alternative plug 232 which is similar to the plug 132, but which is not necessarily formed of an elastomeric material. To render the plug 232 radially expandable, it is formed of circumferentially spaced, flexibly interconnected segments 234. This construction may be achieved by providing the plug 232 with circumferentially spaced radial slots 236 extending from the axially inner end of the plug nearly to the axially outer end thereof, to leave small flexible interconnections 238.

With the foregoing construction, the radially expansible plug 232 may be made of a variety of materials having sufficient flexibility that the interconnections 238 permit the desired radial expansion. For example, various plastic materials can be used.

The same slotted construction can also be applied to a plug, not shown, having essentially the same configuration as the plug 232.

Although exemplary embodiments of the invention have been disclosed for purposes of illustration, it will be understood that various changes, modifications, and substitutions may be incorporated in such embodiments.

I claim as my invention:

1. In a lockable closure for a tank filler opening, or the like, the combination of:

(a) a rigid closure frame having an outer end and having an inner end spaced from said outer end and insertable into the opening;

(b) a radially expandable, annular plug carried by said closure frame adjacent its inner end and engageable, when radially expanded, with the periphery of the opening to lock the closure in the opening;

(c) a central actuator carried by said closure frame adjacent its outer end and movable axially relative to said closure frame from an outer position wherein it projects axially outwardly beyond the outer end of said closure frame and an inner position wherein it is at least approximately flush with the outer end of said closure frame;

(d) plug expanding means connected to said actuator, and responsive to axially inward movement of said actuator from its outer position to its inner position, for radially expanding said plug into closurelocking engagement with the periphery of the open- (e) guide means for said plug expanding means forming part of and interconnecting said inner and outer ends of said frame; and

(f) said guide means comprising circumferentially spaced pins which extend through openings in said plug expanding means and on which said plug expanding means is axially slidable.

2. A lockable closure according to claim 1 including key means engageable with said actuator for pulling same axially outwardly from its inner position to its outer position to release said plug from closure-locking engagement with the periphery of the opening.

3. A lockable closure as set forth in claim 2 wherein said actuator is provided in its outer end with a cavity having therein an inwardly facing shoulder, and wherein 6 said key means is insertable into said cavity and includes at least one projection engageable with said shoulder.

4. A lockable closure as defined in claim 2 wherein said plug expanding means includes circumferentially spaced sectors connected to said actuator at their apices and having their larger ends in engagement with said plug, said sectors forming a cone when said actuator is in its outer position and forming substantially a disc when said actuator is in its inner position.

5. A lockable closure according to claim 4 wherein said sectors constitute a toggle mechanism movable over center as said actuator is displaced from its outer position to its inner position.

6. A lockable closure as set forth in claim 2 wherein the inner surface of said plug converges axially inwardly, and wherein said plug expanding means comprises a disc connected to said actuator and engaging said convergent inner surface of said plug.

7. A lockable closure as defined in claim 2 wherein said plug comprises a plurality of circumferentially spaced, flexibly interconnected segments.

8. A lockable closure according to claim 2 including an annular seal carried by said closure frame adjacent its outer end and engageable with the periphery of the opening.

References Cited UNITED STATES PATENTS 2,214,732 9/1940 Kraft 220-245 2,488,796 11/ 1949 Baier 220-245 3,048,297 8/1962 Elliott et al. 220-245 3,156,373 11/1964 Willis 220-245 3,244,308 4/ 1966 Esposito, Jr 215-52 3,326,403 6/1967 Glass 220-245 JOSEPH R. LECLAIR, Primary Examiner I. R. GARRETT, Assistant Examiner 

